When I was at Decfest 2012 I bought a board (ver 10 2012) to build this amp.
I always wanted to build a kit and this looks like a great place to start.
This is all new to me so I hope to learn a lot with some help from you guys.
I will be ordering the parts soon. Other then what is listed on the parts list are there any other items I need to get?
I will also be ordering a soldering iron from parts express. I have a VOM, solder. Do I need a de solderer sucker or the de soldering braid?
 The instuctions are not very clear as to how to go about building this so if you can list some pointers on how to proceed that would be great.

I have seen some really nice builds shown here and I hope mine comes out just as nice.

Thanks
John

Hey John...

Sounds like you got the new board with the corrected wiring (for the Edcor's), as well as the 100 Ohm virtual CT for the heaters???  These will help a lot.  I'm still working on mine.  I tested the 100 Ohm CT revision, and it did remove most of the AC hum from the heaters.

Be sure you have an alligator clip on you VOM.  Attach it to the grounded side of any component, and use the red lead to test voltages.  Very high voltages...you don't want both hands near the board when powered on!

Take your time!  You will learn a lot!  I know I have.

Mike

If it's not too late, I got the IEC with the fuse holder built in.  Less wiring!  I spent hours trying to figure out why my voltage (D) was so high.  I finally swapped the 6922 tube with a 6N1P, and the voltage dropped to within specs.  Thought I had a bad solder joint or component.  What a relief.  Be sure to mount the big ol' 1K 5W resistor an inch from the board (and everything else).  It gets hot!!!

I plan on installing a standby switch

http://tubedepot.com/p-dpst-3way.html

to let the tubes warm up before feeding the amp the full voltage.  Not required, but worth a Google.

Have you ever soldered before?  If not, and you would like to practice on something, you could buy a prototype board like this

http://www.ebay.com/itm/Vacuum-Tube-prototype-project-board-8-pin-tubes-/1407228...

Solder pieces of wire, unused resistors, etc, 'til you feel a little more comfortable.

I'll to get some pictures, if I can find my wife's camera.

Mike

Oh...I wish I hadn't sold my '71 Chevelle SS 454 when I was younger, but...

John

Here is a picture of my builds.  I soldered the 150 ohm 5W resistor and one of the 10K ohm 5W resistors to the tube side of the board, as it got crowded on the component side.  I plan on replacing the big black 1K 6W resistor, as I failed to allow for the 1 inch clearance.  This is the Rev 9 2011 board...yours should have the correct wiring colors and the 100 ohm virtual tap for the brown heater wires.

Mike

Yep, two amps.  I was going to wire them both mono, but now I'm not sure.  I got them from Keith (Ebay member po1019).  They were already made, and I took a chance that I could fit everything.  It's tight, but I think they will work.  He does great work, and will build any size you need.  Here is a link to his products.

http://www.ebay.com/sch/po1019/m.html?hash=item3a75963758&item=251080882008&pt=V...

Mike

Hey John...

The inside dimensions of the matching pair I bought were ~ 8.25 W, 8 D, and 2.25 H.  The board (I think) is 6 x 6.  Very tight (hope I can pull it off).  The one you are looking at is 6.3125" x 7.25" x 2.0625" internally.  I think that is way too small.

Are you going to mount a separate pot to the chassis?  I cheated.  I used the PCB pot, and drilled a hole in the front of the case where it would poke through after mounting the board to the top of the case...about 1/4" from the front.  This was easier for me (I'm still new at this as well), and gave me 2 inches on one side and the back.

The transformers on top are a little tight as well (I'll try to get more pictures tonite).  I know a lot a others have mounted the OT's in the case.  Again...I hope my idea works!

Anyway, if I were to do this again for a single stereo amp, I'd add 1 to 2 inches in width, and 1 inch in depth.  The 2.25 H is okay...2.5 would be a little better.  Again, an external pot might change things a little???  I'd order a custom one from Keith.  He needs the INTERNAL dimensions, and you could select the wood that you like.  Again, he is wonderful to work with, and they usually take about a week to build.

Give it some thought while you are building the board.  Did you order Edcor transformers?  Mine took a full six weeks to arrive, so you have plenty of time to think about it.

I'm new to this too, but will be happy to help as much as I can.

Mike

Sounds good.  I noticed that the new 100 ohm resistors for the virtual CT for the heater wires were not in the parts list (at least I didn't see them).  If you need a couple, I bought 10 (since they were cheap, but shipping isn't).  I'd be happy to mail you a couple if that helps.

Mike

Good thing I bought extras!  PM me, I'd be happy to send you a couple.  Received the switches yesterday.  DMM shows they should work...will rig up a test to be sure before I stuff everything onto the case.

BTW...here's the top view of the chassis.  Drilled a few more holes today, but taking it slow.  Notice the hole under the PS transformer?  That's what happens when I get tired.  Good thing the transformer covers it up when I remove the spacers.

Mike

John...

PM'd you, missed your request for the resistors.  My bad!  Will get them out tomorrow.

Mike

Mike,
Your parts arrived today.  I think all I need are the transformers.
John

The tranformer arrived yesterday. Bigger and heavier then I thought they would be.
Now that I have all the parts (I thinK) where do I start?

Maybe this could be a newbe guide to building a Zkit 1.

Hello Mike,

I have a capacitor question.
Reguarding the 4, 1uf 400volt metal poly film cap.
Do these cap have polarities? Or does it mater.

My transformers have shipped and I should get them for next weekend.

Have you had a chance to hook up your amp to your Klipschorn?
Real

Thanks Mike,

My board looks much like yours.
I hope I have every thing correct.
I tracked my transformers and should be getting them by next weekend.
I plan on building my own case. I will most likely start on it next weekend.

Lookin' good, guys!  

Odd.  Looks like the new board has a place to solder the white/blue screen wires.  I assume they go nowhere???  I just cut the wires at the transformer.

Keep us updated!

Mike

I am working on the layout tonight and I am wondering if there is a min distance the transformers should stay away from the board?
I am thinking of hanging the board from a steel plate amd mounting the transformers on top. I am looking at an area of approx. 9 x 18.
That looks like I will have more than enough space to work in.

John

My "plate" is 8X8.  

As you can see in post 23, as long as the two holes you drill to pass the wires through the plate are not on top of the board, you should be okay.  My enclosures were a little small, and the first time, I had the PS transformer turned 90 degrees from where it is now.  That's when I realized the wires were above the board, and difficult to work with.

I have an inch clearance between the holes and the board, and had no problem.  Unfortunately, the transformers overlap the board by and inch, so a couple of board mounting screws are under a transformer.  

Reminder.  I was told it is a good idea to turn the PS transformer 90 degrees from the OP transformers.

With my setup, 10 inches wide and 9 inches deep would have been much easier to work with.  Again, I'm using the PCB mounted pot, so the board is 1/8 inch from the front.  If I had used a separate pot, I would have needed more room in front.

Good luck guys!

Mike

Hi John...

Don't you hate learning curves?  I'm glad I started with aluminum...easier to drill.

Did you use step down drill bits?  If not, an investment would do wonders, although I don't know how much they would cost to deal with heavy gauge steel.  You can easily round out the holes, and smooth out the edges.  The holes you drilled for the transformer wires need to be very clean, or do what I did and buy rubber grommets to "snap" inside the holes to prevent cutting the coating around the wires.

I tested my board "outside the box".  Granted, it meant a lot of temporary solders, but I wasn't brave enough to put everything together first.  You may be braver!

The most important ground is attaching the IEC ground to the chassis.  This can save your life.  Drill another hole a couple of inches from the IEC hole, and run a short wire from the IEC ground to a bolt through that hole.  I used a bolt, nut, washer, and lock washer.  I ended up attaching the chassis ground to this as well.  Make sure you scrap any paint from the edges of the hole.  You want a good electrical connection.

I've been told...always twist wires.  I could only twist the heater wires, as everything else had such short runs that I had no room to twist.

If two sets of wires cross, make sure they cross at 90 degrees, if possible.

This part of the project is nerve racking.  Take youe time.

Mike

I can't see anything wrong.  Actually, without the red/black CT wire attached, you could fire it up!  The brown wires are connected, so you should see the tube filaments glow.  That will be cool!  Uh, I mean hot.  Great first test.  There will still be high voltage going thru the diodes, but without the center tap wire connected, the voltage cannot be rectified.  The buck will stop there.  Make sure the loose red/black wire cannot touch anything.  

Now you will understand how to hook up the red/black center tap wire.  Run the red/black wire from the transformer to the second switch.  Run a wire from the other pole of the switch to red/blk on the pcb.  Actually, I'd call the first switch the standby switch, as it will only conduct heater current.  The second switch will power on the amp.

Turn on sequence...

1)  Standby switch on.  Let tubes heat up for 20 to 30 seconds.

2)  Power switch on.  B+ DC current can now flow, because the power supply has a center tap.  Now you can measure test points.

Turn off sequence...turn both off at the same time, or turn off the power switch, followed by the standby switch.

Make sense?

Mike

From Nimrod...scroll to the bottom

https://www.decware.com/cgi-bin/yabb22/YaBB.pl?num=1341162665/all

I used the pots soldered to the board.  Perhaps you could PM him for more specifics.

Mike

Great Job!  Love the red oak.  You may have mentioned this already, but what kind of speakers will this amp drive?

Mike

Well it has been a few months since I finished and I have done a lot of listening. I am really happy with the results. While the amp doesn't have the power my SA-12 has, I can get my Proac Tabeletts to an good listening volume. I did have a friend bring over her Klipisch Heresy speakers. Now that was the ticket. She was amazed how a 2 watt amp could "get so much sound out of them". We played music until 3:00 AM
What was really crazy her kids in their 20's never saw a LP or a turntable before.